The condition of the year’s corn crop varies from looking good to drowned out. Many of the growth problems are associated with the amount of rainfall received and the drainage for each field; the better the drainage, the better the crop appearance.
During May 2013, the Ag 10 Research Center received 8.75 inches of rain, which is twice the normal amount for May. In the more poorly drained areas, the corn height is significantly shorter—one growth stage smaller—and the color of the corn is a lighter green. There are two principle reasons for these observations.
First, the applied N has moved out of the current rooting zone for the corn crop due to this excessive rainfall.
Secondly, the nodal root system, the principle root for the corn plant, is smaller than normal and reduced nutrient (N) uptake is occurring. This reduction in root growth is caused by cool weather, too much water, lack of oxygen in the root zone, and the lack of nutrient uptake (N, K, and S).
This is possibly a good season to strongly consider a sidedress application of 30-to-50 lbs. N/A. I would suggest the following N sources be considered:
- Nitrogen plus sulfur.
- 32% UAN.